help with overall length

[declinetostate]

I have a glock 33 with a .40 conversion barrel and I'm having trouble with my reloads. I've been trying to reload some 180 grain cast lead bullets over 4.3 grains of bullseye. All the info I find says minimum OAL is 1.125. When I take the loaded bullet and set it into the barrel it seems too long. It feels like the bullet is hitting the edge of the chamber. The gun runs on cheap federal FMJ which are 180gr With an OAL of 1.120. I build a dummy at that OAL and it seats properly. Is it ok for me to knock the OAL to 1.120? If so do I need to reduce the powder load? I'm really new to this so any help would be great. Thanks in advance.

[noylj]

Only you and your gun can determine what COL is needed. It sounds as though residual case mouth flare is not the problem. Did you mark the bullet and case with a Sharpie to determine where the contact actually is?

In your case, you are only going 0.005" shorter. Is your set-up so perfect that your basic tolerance for COL using a cast lead bullet will not vary by that much and, more likely, more? I know my presses have never held that tight a tolerance and my guns have never known the difference.

You need to worry about bullet set-back of 0.01". My concern is that you will produce rounds that are longer, given the variations in cast bullets, and not chamber. I show 1.120-1.135" as recommended COL, so you aren't going into uncharted territory.

It is very good to make up a dummy round or two to prove your set-up. You will start at the starting load and work up. If you actually are concerned, simply drop the starting load by 0.3gn and work up. Load about 20 rounds at the starting load and verify function at the range. Right now it sounds as though you have a tight match chamber and may need to reduce your COL even a bit more so the normal tolerance for COL will still have all rounds chamber.

[Jman]

What lead bullet shape are you using? They wouldn't be semi-waddcutters would they?

Edited January 1, 2011 by Jman

[G-ManBart]

SAAMI minimum is 1.085". That doesn't mean that any listed load is safe at 1.085", but it is a reference point.

You say it feels like the bullet is hitting the rifling...is there a mark on the bullet? Are you sure your crimp measurement is correct (something around .420" or so)?

Lyman shows a cast lead 175gr bullet at 1.125" and a max of 5.1gr of Bullseye. They also show a different cast lead 175gr bullet at 1.100" and a max of 5.0gr of Bullseye, so you should be fine if you have to shorten that load a little bit.

Once you have a couple of good manuals, get a copy of Loadbooks One Book/One Caliber...it has most major bullet and powder manufacturer's data all in one place, for something like $15...well worth it. The manuals are still necessary to help explain and serve as a reference for questions other than data...unfortunately, a lot of people just use the internet, and then run into problems that most any manual would explain...just sort of the way it is. R,

Bart